You can imagine a system where loads with the ability to vary their draw do so automatically in response to grid frequency changes, without even needing a centr

You can imagine a system where loads with the ability to vary their draw do so automatically in response to grid frequency changes, without even needing a centralized bidding system. Frequency regulation is, however, a relatively small amount of power, and the grid itself needing to run at a particular frequency is more the result of loads that rely on the grid frequency for timing (i.e. A/C electric motors in fans). In the future the grid frequency could be allowed to vary much more if loads become resilient to frequency variations. The bigger (in terms of total energy) issue is shifting load to match supply, or vice versa. That can be achieved with appliances that store energy in one form or another. One of the most interesting examples of this is generating ice with wind energy at night to be used for cooling during the day.